package com.bumptech.glide.load.resource.bitmap;

import android.graphics.Bitmap;
import android.support.annotation.NonNull;

import com.bumptech.glide.load.engine.bitmap_recycle.BitmapPool;
import com.bumptech.glide.util.Util;

import java.nio.ByteBuffer;
import java.security.MessageDigest;

/**
 * A {@link BitmapTransformation} which rotates the bitmap.
 */
public class Rotate extends BitmapTransformation {
    private static final String ID = "com.bumptech.glide.load.resource.bitmap.Rotate";
    private static final byte[] ID_BYTES = ID.getBytes(CHARSET);

    private final int degreesToRotate;

    /**
     * @param degreesToRotate number of degrees to rotate the image by. If zero the original image is
     *                        not modified.
     */
    public Rotate(int degreesToRotate) {
        this.degreesToRotate = degreesToRotate;
    }

    @Override
    protected Bitmap transform(
            @NonNull BitmapPool pool, @NonNull Bitmap toTransform, int outWidth, int outHeight) {
        return TransformationUtils.rotateImage(toTransform, degreesToRotate);
    }

    @Override
    public boolean equals(Object o) {
        if (o instanceof Rotate) {
            Rotate other = (Rotate) o;
            return degreesToRotate == other.degreesToRotate;
        }
        return false;
    }

    @Override
    public int hashCode() {
        return Util.hashCode(ID.hashCode(),
                Util.hashCode(degreesToRotate));
    }

    @Override
    public void updateDiskCacheKey(@NonNull MessageDigest messageDigest) {
        messageDigest.update(ID_BYTES);

        byte[] degreesData = ByteBuffer.allocate(4).putInt(degreesToRotate).array();
        messageDigest.update(degreesData);
    }
}
